The invention described herein relates to the field of therapeutic devices attachable to the joints of the human body, in particular corrective devices for attachment to the leg of below-the-knee leg amputees for correcting flexion contractures of the knee joint.
As a consequence of their illnesses and injuries or indirectly from curling up in reaction to the phenomena of phantom pain, many below-the-knee amputees suffer from flexion contracture of the knee joint. In this condition, the knee joint stays flexed or bent, resists movement, and the patient does not enjoy the normal full range of mobility. For amputees this is a particularly troublesome problem because the contracture impedes the process of fitting them with a suitable prosthetic device. The length of the prosthesis and its load bearing structure are affected by the position of the knee and residual limb. If an improvement in a knee contracture condition takes place subsequent to fitting the patient with a prosthesis, a retrofit or replacement may be required. Since prosthesis are generally custom designed and built, this can be quite costly. Therefore, it is customary to treat any knee flexion contracture soon after the amputation and before the prosthetic device is designed and built.
However, existing means and methods for treating knee flexion contractures have not proven to be well adapted to the needs of amputees or their care providers. One common means of treating knee contractures is with bandages and plaster of paris casts. A series of plaster casts are applied between conventional physical therapy sessions. The process is time-consuming, messy, and expensive. Furthermore, while the physician is typically concerned about the possibility of infection at or near the site of the amputation, the area of concern is usually obscured from view by the plaster cast.
Some occupational therapists lay the leg in a trough or gutter to passively accommodate the joint in hopes that mere gravity will eventually return full extension to the knee. Various elastic bandages and knee braces or immobilizers are known to be applicable to knee contractures, but these devices are not well suited for use by leg amputees. The residual limb of an amputee normally extends only about six to nine inches below knee center and such devices typically cover the amputation site, obscuring possible infections and the like from the view of the care provider. Many of the conventional devices also apply unwanted pressure on the residual limb. The residual limb is usually quite sensitive to any contact for some time after the amputation surgery. Finally, many of the existing devices must be custom fit and are therefore quite expensive.
Therefore, it is a primary object of this invention to provide a leg amputee knee corrective orthosis which can be applied at the conclusion of the amputation surgery to passively stretch the joint and yet allow the physician easy access to examine the residual limb without destroying the orthosis.
A further object of this invention is to provide an orthosis which provides an easily adjustable amount of passive corrective tension to the knee joint.
A further object of this invention is to provide a leg amputee knee corrective orthosis which is quickly and easily adjustable to fit various patients, yet capable of being mass produced rather than custom made.
A further object of this invention is to provide a single leg orthosis which can be used on either the right or left leg of the patient.
A further object of this invention is to provide an orthosis which is quickly and easily attached to the leg of an amputee without the use of messy plasters and the like.
A further object of this invention is to provide an orthosis which is durable in use and economical to manufacture.
A further object of this invention is to provide an orthosis which accommodates, controls, and helps ease post-surgery swelling or edema.
A further object of this invention is to provide an orthosis through which drainage tubes can be attached to the residual limb, if needed.
A further object of this invention is to provide an orthosis with a lower end which can accommodate a prosthesis or artificial limb.
A further object of this invention is to provide an orthosis which has padding under the patella to absorb some of the forces which the underlying tendons are subjected to by the patient's prosthesis during ambulation.
A further object of this invention is to provide an orthosis having a soft, absorbent liner and cuff which render the orthosis comfortable to wear.
These and other objects will be apparent to one skilled in the art from the description which follows.